In response to Suntiger's posting, I thought I'd lay out what I've figured out for cold weather outdoor walking. I would encourage others to add their suggestions too!!
This may be too extreme for those of you who do not live in a climate like (or colder than) mine, but you may find parts of it useful. I live in central Massachusetts USA, where summers are 80s/90s and humid, and winters have 15 or so days of single digit temps (F). Every couple of years we have a few days below 0 F. Plus everything in between. Garden zone 6a. Fair amount of rain all year, from tropical downpours in summer to icy nasty stuff in winter.
I run much colder than normal people.
I do an outdoor walk daily, all year round, usually first thing in the morning, for about an hour. Since I retired it's become my thing. I walk on "country roads" meaning narrow paved roads with no sidewalks, in a residential neighborhood. I sometimes have to get off the road onto grass, dirt, gravel, snow, or poison ivy when cars or trucks go by. I walk in all kinds of weather. The only time I don't go out is during the part of a snowstorm where plows are out. Too dangerous to play chicken with a snowplow I wear exclusively fitness gear for this, and because one of my personas is sporty natural, I have built up quite a good collection over the years for all seasons. I buy mostly the brands known for quality outdoor gear, which lasts for many years, and am partial to LL Bean, although I have also had good luck with Eddie Bauer and Columbia. I haven't tried Athleta but probably good. If a brand carries petite sizes I've probably tried them.
For underlayers, I find fleece warmer than merino, and have tried both. I find merino a little itchy although manageable, but fleece is soft and comfy. Merino used to require more careful laundering but not so true today. Fleece also tends to be less expensive. For maximum warmth look for fleece on the inside as well as the outside. I'm partial to Uniqlo because they hold up well and are relatively inexpensive. The last time I tried silk I found it NOT very warm, but I know lots of people love it.
I put my biggest investments into footwear and gloves and to a lesser extent hats. If feet, hands, and head are good in frigid weather, the rest is much easier.
Suntiger, for your climate in mid Atlantic US (right?), for an outdoor walk or hike in winter, I would think you could do well if you got a fleece underlayer, a warmer fleece jacket, and an outer layer that is wind/waterproof with a hood. Hats, gloves, scarves, maybe a puffer vest as needed. Getting a collection of layers will give you the most options for different temps etc and let you experiment to find what works. And the right footwear of course, that is actually the highest priority.
Below is a list of ALL the layers I wear in early Feb, to give you some ideas. Remember I'm in a cold climate, I run incredibly cold, Feb is the coldest part of the year, and I'm out at first light.
Uniqlo Heattech fleece turtleneck. They now make three different warmth levels for Heattech and I can't wait to try the heavier weights.
Purple Columbian fleece zip jacket. Mid-weight.
Black LLBean heavier weight fleece jacket. Have had this one for 20+ years.
Eddie Bauer "parka" that is water/wind resistant and has a light weight quilted lining. Also 20+ years. Used to wear this over a light layer for cross country skiing.
Kit hat. Has to be snug, with a tight and heavy knit so the wind won't blow through it. Like what downhill skiers wear. Most "fashion" knit hats don't cut it for me. I wear these two layered together and also have a couple of other options.
thick fleece neck gaiter - MUCH better than a scarf, pulls up over my nose and stays there, no fussing with getting it placed just right., wind resistant. This is GAP kids, found at a thrift store. And it's animal print! LOVE!
Insulated downhill ski gloves. This year I plan to try the battery heated ones hunters wear, because even with disposable heated packs added my fingertips are cold and painful in these gloves in the coldest weather when I'm out for an hour. Maybe I have Renaud's.
Merrill waterproof insulated snow boots that are structured for walking/hiking. I can wear these walking across shin-to-knee deep snow without any trouble except that my thigh muscles feel it later Finding the right brands that work for YOUR feet is well worth the time and money investment. My feet have felt sooo warm and good in these boots.
SmartWool mid weight socks.
....and for rainy days all year round, my 25year old LLbean hooded long raincoat. It's totally waterproof, lightweight, and I sized up so I can fit warm layers under it. It supports my NO EXCUSES approach. For example, in summer, worn with waterproof shoes, the only parts of me that get wet are face, hands and ankles, and I can live with that! There were not as many waterproof fabrics around when I bought this, today there are tons of options.